Marinelife in the Aegean - Turkey - Glossary

Abdomen	A group of up ten segments behind the thorax of crustaceans which sometimes have appendages.
Adult	A fully developed and mature individual, capable of breeding but not necessarily doing so until social and/or ecological conditions allow.
Algae	Very primitive aquatic plants.
Annelid	A ringed or segmented worm.
Antennae	The second pair of sensory appendages of crustaceans, usually long and slender.
Antenules	The first pair of head appendages of crustaceans.
Anterior	More to the front.
Aquatic	Associated with or living in water.
Anthropod	An invertebrate such as a crustacean with a chitinous, jointed exoskeleton and paired jointed limbs.
Asymmetrical	Without symmetry, irregular or unequal, used to describe some animals such as sponges.
Benthic	Dwelling in or on the bottom of the sea.
Bilateral Symmetry	Symmetry of an organism where one half is a mirror image of the other.
Bivalve	A shell or protective covering in two hinged parts encasing a body.

Calcareous	Composed of or containing calcium carbonate.
Carapace	The dorsal shield of the exoskeleton covering mainly the anterior part of the body of most crustaceans.
Carrion	Dead and decaying flesh which is eaten by scavengers.
Carnivore	An animal that feeds on other animals.
Cell	The smallest functional unit of a plant or animal, consisting of a nucleus surrounded by cytoplasm and bounded by a membrane, and sometimes a cell wall.
Cephalopod	A mollusc which has a large well developed head surrounded by tentacles, and a large mantle cavity. Propulsion is achieved by water being ejected from the mantle via a siphon.
Cephalothorax	The fusion of head and anterior thoracic segments in advanced crustaceans to form a single body region.
Chela	The leg of crustaceans bearing a pincer like tip.
Chitin	The organic constituent of cuticle forming the external "shell" of anthropods.
Cilia	Minute filament like structures which, by beating, create a current and provide locomotion, not visible to the naked eye.
Class	The major subdivision of a Phylum classifying similar orders of organisms.
Cnidarian	Cnidarians (pronounced Cnidarians) are flower like in appearance with tentacles to trap food, they have stinging cells and come in a wide variety of often bright colors, species include Anemones, Corals and Jellyfish.
Colony	An organism consisting of a number of individual members in a colonial association.
Colonial	Living together in a colony.
Community	A group of different organisms inhabiting a common environment.
Compound eyes	The type of eyes possessed by most crustaceans composed of many long, cylindrical units, each of which is capable of light reception.
Crab	Ten footed crustacean with the first pair of legs modified into pincers.
Cuticle	The exterior layer of the skeleton of anthropods formed of Chitin and protein, may be tanned.
Crustacean	A large class of anthropods with hard shells, mainly aquatic, see Crab, Lobster, Shrimp.
Cytoplasm	Protoplasmic content of a cell other than the nucleus.
Decompression	The gradual return of divers from the high pressure environment under water to normal atmospheric pressure at the surface.
Denticles	Small tooth like scales.
Detritus	Particles of decaying organisms forming the food of many other organisms.
Disc	The mouth disc of an anemone which bears the tentacles.
Dispersal	The movement of individuals away from their home range.
Dorsal	Upper side or back of an animal, generally directed upwards.
Dorsal fin	The fin on the back of a marine organism.

Echinoderm	Animal of phylum Echinodermata, includes starfish and sea urchins.
Ecosystem	A community of organisms within an environment interacting with one another and the environment in which they live.
Ectoparasite	A parasite living on the outer surface of its host.
Endoskeleton	An internal skeleton, as in echinoderms and vertebrates.
Exoskeleton	An external skeleton, as in crabs and lobsters.
Family	The major subdivision of an Order classifying similar Genera of organisms.
Filter feeding	The process whereby certain organisms obtain food from the surrounding water by filtering.
Free living	Living an independent lifestyle unattached to any other structure.
Genus	The major subdivision of Families classifying similar Species of organisms, many genera may form one Order.
Gills	The respiratory organ of aquatic animals.
Gill slits	The slits between the gills that allow the water through.
Herbivore	An animal that feeds on plants.
Hermaphrodite	An organism that has the reproductive organs of both sexes.
Holdfast	The attachment organ of seaweeds.
Interstitial	The flora and fauna living between sand particles.
Invertebrate	An animal which lacks a skeleton of either bone or cartilage.

Kingdom	Domain, a province of nature
Littoral fringe	The shoreline zone whose upper and lower limits are defined by the highest point that periwinkles occur and the highest point that barnacles occur respectively.
Lobster	Large marine stalk-eyed ten footed long tailed edible crustacean of the family Homaridae with large claws formed by the first pair of legs.
Mandible	The paired appendages behind the mouth of anthropods.
Medusa	The free swimming stage of the cnidarian life cycle.
Mollusc	A member of the phylum of invertebrates that includes bivalves, squid and octopus.
Molt	The periodic shedding of the anthropod exoskeleton to allow growth until the adult stage is reached.
Multicellular	Composed of a large number of cells.
Nematocyst	The barbed coiled threads released from the ovoid cell of cnidarians which ensnares and stings its prey.
Nocturnal	Animals which are awake and active by night.
Nucleus	Dense central part of a plant or animal cell, containing genetic material.
Nudibranch	A marine mollusc which has a naked dorsal gill.
Omnivore	An animal that feeds on both animals and plants.
Oral	Relating to the mouth.
Order	Major subdivision of Class.
Ovoid	Oval shaped with one end more pointed than the other.

Parasite	An organism that lives on or in another drawing nutrient directly from it.
Pelagic	Organisms inhabiting the surface waters of the sea.
Phylum	A subdivision of a 'kingdom' classifying similar 'classes' of organisms.
Physiology	The study of the processes that occur within living organisms.
Phyphotoplankton	Microscopic algae suspended in surface waters where sufficient light exists for photosynthesis to take place.
Plankton	Swimming or drifting, often minute or microscopic, organisms which live freely in the water.
Polyp	A sedentary, individual cnidarian with a tubular, sac like body attached to the substrate and the oral end bearing the mouth and tentacles.
Predator	An animal that forages for live prey.
Radial symmetry	The symmetry of an organism in which the body parts are arranged around a median vertical axis.
Ray	The radial division of an echinoderm, ie arm of a starfish.
Rostrum	The pointed projection at the extreme anterior end of the head of a crustacean.

Salinity	The measure of the salt content of water.
Scale	A flat plate forming part of the external covering of most fish.
Scuba	Acronym for Self Contained Underwater Breathing Apparatus, consisting of a cylinder containing high pressure air and a device to reduce the delivery pressure to ambient water pressure, thus allowing divers to breathe normally and independently underwater at varying depths.
Sedentary	Organisms which are attached permanently to the substrate or while attached to the substrate during part of their life cycle.
Segment	A repeating unit of the body.
Sessile	An organism living attached to substrate or to the 'shell' of another organism.
Shrimp	Small aquatic edible decapod crustacean.
Siphon	A tube leading into or out of certain organisms used for transferring water in and out of the body.
Species	A reproductively isolated group of interbreeding organisms. Similar species make up a 'genus'.
Swell	The undulating movement of the surface of the open sea.
Swim bladder	An air sac lying between the gut and the backbone of some fish and is used primarily to control buoyancy.
Symbiotic	The close and often, but not always, mutually beneficial relationship between individuals of two different species.

Territory	The area that an organism considers its own and defends against intruders.
Test	The internal skeleton below the epidermis of some invertebrates, ie. sea urchins.
Thermocline	The narrow, often abrupt, transition zone between upper warmer water and the deeper colder water.
Thorax	The segmented body region of crustaceans which lies behind the head and which typically bears locomotory appendages.
Tube foot	The hydraulic appendage of echinoderms connected to the water vascular system, may serve as limbs and bear suckers.
Tunic	A form of cellulose surrounding the bodies of sea squirts.
Upwelling	The circulation of colder, often nutrient rich, waters to the surface caused by convection or wind.
Ventral	The underside of a bilaterally symmetrical animal.
Vertebrate	An organism with an internal skeleton of bone and cartilage.


Marine Life in the Southern Aegean Sea A GUIDE FOR DIVERS and SNORKELERS VISITING TURKEY	Author: Cliff Fraser PADI Master Scuba Trainer